1. Field of the Invention
This invention relates to a safety switch system. More specifically, this invention relates to an improved safety switch system for use in hydroblasting and hydrocutting operations.
2. Description of the Prior Art
High pressure water is used for a number of purposes. For example, in the more traditional applications of hydroblasting operations, it is used to clean industrial and commercial equipment such as heat exchangers in refineries, concrete pads and runways, and other commercial applications. In performing these cleaning operations, it is not uncommon to eject water at pressures on the order of 6,000-20,000 psi. Furthermore, water is used in hydrocutting operations to cut metal, glass and other materials. When performing these operations, water is typically pumped and ejected at pressures on the order of 30,000-40,000 psi.
In either event, pressures at these levels can cause serious injury to an operator. Therefore, there is a need in the industry to improve the safety of hydroblasting and hydrocutting equipment used in close proximity to the operator.
The prior art discloses a number of safety mechanisms used on hydroblasting guns. Such prior art systems typically comprise the use of a mechanical lever or an electric switch in combination with a trigger. See, for example, U.S. Pat. Nos. 3,885,739; 4,216,911; and 4,802,313. U.S. Pat. Nos. 4,216,911 and 4,802,313 disclose the use of a mechanical lever which must be depressed to make a trigger operable. U.S. Pat. No. 3,885,739 discloses the use of an electric switch which must be engaged to make the trigger operable. However, these prior art devices can be tiresome to continuously operate and are not ergonomically designed. This can lead to early fatigue which can cause accidents.
Therefore, the need exists in the industry for an improved system which is easy and comfortable to activate for prolonged periods of time without undue fatigue.